The following background material includes information that may be useful in understanding the present teaching. It is not an admission that any of the information provided herein is prior art, or material, to the presently described or claimed disclosures, or that any publication or document that is specifically or implicitly referenced is prior art.
L-lysine is an essential amino acid that is supplied as a feed supplement for both monogastric and ruminant animals. lysine feed supplements are commercially supplied in essentially three forms—as dried granules of lysine-HCl salt (often called merely lysine HCL), as a dried broth from a fermenter from which the lysine was made by bacterial fermentation (often referred to as lysine sulfate because the predominant form of the lysine from a dried broth is as a sulfate salt) and finally as free lysine that is supplied as liquid solution to be sprayed onto animal feed as a supplement (often called lysine freebase). There are minor variations in some compositions of these three forms of lysine feed. For example, lysine HCl granules may include minor amounts of anti-caking agents to improve flow properties, dried lysine sulfate may or may not include the bacterial cell mass from the fermentation broth, and lysine freebase may be supplied in different liquid concentrations.
Each of the three forms of commercially available lysine feed supplements have advantages and disadvantages. Some advantages of lysine HCl are that the dried granules are relatively speaking, pure, inexpensive to ship, easy to control in terms of production specifications, and have low hygroscopic character. The major disadvantages are that it is costly to make because it requires purification and crystallization of lysine from a fermentation broth, and only 80% of the weight of the product is lysine—the remainder being the HCl. The major advantage of lysine sulfate is that it is simplest to make, however, its disadvantages are that the product has variable composition because it is simply a dried fermentation broth, and for the same reason is relatively impure, with typically no more than 50% of the dry weight of the product being lysine. The major advantages of lysine freebase are that the lysine product in solution high purity, and the ease of shipping and handling a liquid. The major disadvantages of lysine freebase is that because it is provided as a solution, shipping costs on a lysine content basis are higher than for the other dry products, and that dedicated mixing equipment is needed to dispense the product onto animal feed.
lysine may also be used in the agricultural industry as a fertilizer. The nitrogen content of lysine is sufficient for practical use as fertilizer, which has the advantages of being organic, biodegradable and a source of nutrition for soil microbes. lysine alone, however, lacks other mineral ingredients such as potassium and phosphate that are often added to a fertilizer. The same advantages and disadvantages of the three forms of lysine mentioned above apply equally when the product is used as a fertilizer.
Although it would seem desirable to sell lysine freebase as a dried product to lower shipping and production costs, from a commercial standpoint such a product is not desirable because lysine freebase is much more hygroscopic than lysine HCl or lysine sulfate, causing the product to cake, swell and loose the free flowing properties that make a dried product easy to manage and dispense. There is therefore, a need in the art to provide a dried lysine feed product that has at least some of the advantages of lysine freebase but without the disadvantages that make such a product undesirable.
The present disclosure addresses this need and others that will be apparent from the disclosure that follows.